Infrared input/output ports for computers allow a wireless connection between the computer and various peripheral devices such as scanners, printers, or personal data organizers (e.g. Sharp Wizard(copyright), PalmPilots(copyright), etc.) The infrared transceiver uses the infrared spectrum for point-to-point data communication, and is typically connected to a computer input/output bus, such as ISA or PCI, through an infrared link controller. Infrared link controllers have evolved from simple Universal Asynchronous Receiver and Transmitter (UART) designs into complex Direct Memory Access (DMA) engines with various logic to support synchronous data transmissions at higher data rates.
An infrared port is not uncommon on desktop computers. Laptop computers will typically provide at least one infrared port. Generally, the transceiver and link controller operate according to the well known standard published by the Infrared Data Association (IRDA) (hereinafter referred to as IrDA) and together the transceiver and link controller implement an IRDA port. For point-to-point IrDA connections between two devices (e.g. a computer and a peripheral device), an awkward orientation of either device may be required in order to achieve a connection therebetween. For instance, if the IRDA port of a laptop exists on its right side, then a peripheral device and its IrDA port must also be located on that side. Prior art attempts to eliminate this equipment layout problem for laptop computers have included locating an additional IrDA port at the opposite end of the laptop""s existing IrDA port. However, this approach creates additional problems in that power usage increases. An IrDA transceiver, which is required for each port, has a dynamic operating current which can average around 100 milliamperes (mA) with a peak current of 1 ampere (A). Since power conservation is very important with laptop computer operation due to fact that such computers usually operate on rechargeable batteries, such power dissipation may be unacceptable for prolonged periods of time.
Prior art attempts to reduce the power consumption demands of dual infrared transceiver laptop computer designs have included enabling and disabling infrared ports at the user level. This solution requires the computer user to be involved in decision making with respect to infrared peripheral device discovery, and adds complexity to the overall infrared communications experience.
A need exists to solve the foregoing problems associated with dual IrDA ports on computers.